DEVELOPMENT OF AN EJECTOR PUMP ENGINE FUEL FEED SYSTEM

An ejector pump engine fuel feed system was designed and developed. The system consists of an ejector fuel pump and a fuel tank sump with a swirl jet and a flexible fuel pickup tube. Several types of ejector pumps were tested which included the simple ejector, a dual series induced flow ejector, a parallel induced flow ejector and a dual operation ejector with two concentric nozzles. An annular ring-type nozzle was tested in addition to the normal central nozzle. The system as developed will pump JP-4 or JP-5 fuel at temperatures up to 200 F to an engine at a flow rate of 70,000 pounds per hour with a pump discharge pressure of 34 psia. The swirl jet in the sump tank provides fluid rotation and a resulting radial force to position the fuel at the wall of the sump tank at all times. This insures that fuel will be at a known location during periods of zero gravity. The fuel is then delivered to the ejector pump through a flexible hose-type fuel pickup tube. The end of the pickup is normally on the bottom at the tank wall. During periods of negative gravity, the pickup will bend upward to draw fuel from the top of the sump area. Flight tests were conducted on a scale model of the sump swirl system to demonstrate the zero gravity provisions.